光声成像技术及其在乳腺肿瘤诊断中的应用

光声成像作为一种新兴的生物医学成像技术, 以光声效应为成像基础, 兼备光学高对比度、超声高穿透度的优点,同时具有光谱信息获取能力,可进行功能成像,具有良好的临床应用前景。乳腺肿瘤是目前光声成像技术临床应用最广泛的领域,本文综述光声成像技术特点及其在乳腺肿瘤的临床应用现状,并对未来应用前景进行展望。     

光声成像技术及其临床应用

光声成像作为一种新兴的生物医学成像技术,以光声效应为成像基础,结合光学成像对比度高、光谱特异度好、声学成像空间分辨率高和穿透力强的特点,具有广泛的临床应用前景。本文从光声成像基本原理、成像模式、在临床医学领域的应用前景以及目前存在的技术局限等方面进行详细介绍。     

6种影像学技术在致密型乳腺诊断中的应用

乳腺癌居于我国女性恶性肿瘤发病的首位,严重危害女性健康。致密型乳腺是乳腺癌的风险因素之一。在致密型乳腺中早期发现、早期诊断乳腺癌非常重要。乳腺X线摄影因受组织重叠、致密腺体遮盖等影响,对致密型乳腺病变检出存在一定局限性。近年来不断发展的功能成像技术,如动态对比增强磁共振成像、弥散加权成像、正电子发射计算机断层显像、乳腺专用伽马成像,通过反映肿瘤血流动力和代谢的变化从而提高致密型乳腺病变的检出。同时,新兴的光声成像技术能提供生物组织结构信息与功能信息,在深层组织中空间分辨率高,其在乳腺疾病中的应用逐渐受到重视。本文对数字乳腺三维断层摄影、超声检查、MRI检查、PET/CT检查、BSGI检查及光声成像等几种影像学检查方法在致密型乳腺诊断中的应用进行综述,为临床医生对致密型乳腺疾病的早期诊断提供帮助。      

多功能光声成像造影剂的研究进展

光声成像是一种新兴的生物医学成像模式,在临床及生物医学研究领域具有重要的应用价值。将光声与其他成像技术及治疗方式结合起来制备的多功能光声成像造影剂是当前国内外研究的前沿与热点,本文就目前这一领域的研究进展进行综述。     

光声成像分子造影剂

光声成像是利用光声效应成像的新型影像技术, 具有光学成像高对比度和超声成像高穿透力的优势。光声成像分子包括内源性生色团和外源性造影剂, 其中外源性分子造影剂的应用, 使分子光声成像成为可能, 因而具有广阔的生物医学应用前景及重要的研究意义。本文对光声成像外源性分子造影剂的物理化学性质及合成方式进行综述, 重点介绍小分子有机染料、贵金属纳米颗粒、碳纳米材料、有机纳米多聚物、基因编码的生色团、铜铁化合物、半导体多聚物纳米颗粒等光声信号复合物及常见的配体分子, 如小分子、肽类、亲和小体、适体和抗体等, 并对未来本领域的相关研究进行展望。     

超声弹性成像对乳腺良恶性肿瘤的诊断价值

超声弹性成像（ultrasonic elastography,UE）作为超声诊断的最新技术之一,在乳腺良恶性肿瘤的鉴别诊断中具有良好的应用前景[1-2]。本文应用超声弹性成像鉴别乳腺病变的良恶性,并以术后病理结果为诊断标准,评价超声弹性成像诊断乳腺肿瘤的灵敏度、特异度和准确率。     

超声弹性成像在乳腺疾病诊断中的研究进展

超声弹性成像技术(UE)以生物组织的弹性(或硬度)与病灶的生物学特性相关为理论基础[1],利用声辐射力弹性成像原理,可以定性、定量地对于组织的弹性特征进行准确评估,是目前临床中非常重要的诊断手段之一,尤其是在女性乳腺疾病的诊断中的应用程度越来越高。本文将针对UE在乳腺肿瘤临床诊断中的应用进展进行综述。     

光声成像在前列腺癌诊断和治疗中的研究进展

光声成像(photoacoustic imaging PAI)是一种新型的非电离式和非侵入式的成像方法,具有高分辨率实时血管显像和在不使用外源造影剂的情况下获得血氧饱和度等信息的特性,并能与超声等成像技术结合,因此在临床各个学科中能很好地应用。目前光声成像技术在前列腺癌的诊疗研究中发展迅速,本文将主要对光声成像技术在前列腺癌诊断和治疗方面的研究进展进行综述。     

超声弹性成像在乳腺良恶性结节诊断中的应用进展

超声弹性成像作为一种新兴超声技术，在诊断乳腺、甲状腺、前列腺等疾病方面日渐成熟。目前主要用于乳腺疾病诊断的超声弹性成像包括静态/准静态弹性成像、声辐射力脉冲成像以及剪切波弹性成像。本文对上述弹性成像技术原理进行介绍，并对其在乳腺良恶性结节鉴别诊断领域中的应用进展及临床应用可靠性加以总结和分析，为临床诊断提供一定的参考意义。      

超声弹性成像对乳腺实性肿瘤的初步研究

目的评价超声弹性成像新技术对乳腺实性肿瘤定性诊断的意义。方法对2005年3月～2005年5月34例（共37个病灶）乳腺实性肿瘤患者进行超声扫查，同时进行弹性成像。对照术后病理结果回顾性分析乳腺实性肿瘤超声弹性成像的特点。结果（1）乳腺癌弹性成像评分多为4、5分，纤维腺瘤多为1、2分，评分分布具有极其显著的统计学意义（P〈0．001）；（2）超声弹性成像中乳腺癌病灶前方出现较宽红晕，纤维腺瘤红晕较细，部分沿着包膜分布。红晕宽度在乳腺癌和纤维腺瘤两组病例中具有统计学意义（P〈0．001），可以作为乳腺良恶性肿瘤鉴别的要点之一。结论超声弹性成像在乳腺实性肿瘤的诊断中具有独特优势和广阔的应用前景。     

Handheld miniature probe integrating diffuse optical tomography with photoacoustic imaging through a MEMS scanning mirror

We describe a novel dual-modality imaging approach that integrates diffuse optical tomography (DOT) and photoacoustic imaging (PAI) through a miniaturized handheld probe based on microelectromechanical systems (MEMS) scanning mirror. We validate this dual-modal DOT/PAI approach using extensive phantom experiments, and demonstrate its application for tumor imaging using tumor-bearing mice systematically injected with targeted contrast agents.OCIS codes: (110.6960) Tomography, (170.0110) Imaging systems, (170.5120) Photoacoustic imaging     

Photoacoustic imaging of the spatial distribution of oxygen saturation in an ischemia-reperfusion model in humans

Photoacoustic imaging (PAI) is a novel hybrid imaging technique that combines the advantages of optical and ultrasound imaging to produce hyperspectral images of the tissue. The feasibility of measuring oxygen saturation (sO₂) with PAI has been demonstrated pre-clinically, but has limited use in humans under conditions of ischemia and reperfusion. As an important step towards making PAI clinically available, we present a study in which PAI was used to estimate the spatial distribution of sO₂ in vivo during and after occlusion of the finger of eight healthy volunteers. The results were compared with a commercial oxygen saturation monitor based on diffuse reflectance spectroscopy. We here describe the capability of PAI to provide spatially resolved picture of the evolution of sO₂ during ischemia following vascular occlusion of a finger, demonstrating the clinical viability of PAI as a non-invasive diagnostic tool for diseases indicated by impaired microvascularization.     

光声成像在肿瘤诊断和治疗中的研究进展

癌症一直是困扰人类的一大难题，常规成像方法在肿瘤的诊断上存在一定的局限。光声成像作为目前医学影像研究的新热点，相比于常规影像方法，它可以利用内源性对比剂如黑色素和血红蛋白，实时且无创地监测与肿瘤血管生成相关物质的浓度，或者通过分子靶向性外源性造影剂与抗体或多肽结合，提供关于肿瘤结构及其分子信息，从而实现形态及功能成像。近年来，光声成像为癌症的早期诊断、肿瘤血管生成的研究、肿瘤微环境的探测，以及癌症进展和治疗反应的监测做出了有价值的贡献。根据光声成像在肿瘤成像上展示出的独特优势，本文就此种医学成像方法在癌症诊断、分期和治疗指导中的应用进展进行综述。      

光声成像技术在心血管领域的研究进展

光声成像（PAI）同时具有光学成像和超声成像的优点,有望解决现有心血管成像技术的难题,准确、全面地提供心血管信息。本文对PAI技术在心血管领域的研究进展进行综述。     

Multimodal characterization of compositional, structural and functional features of human atherosclerotic plaques

Detection of atherosclerotic plaque vulnerability has critical clinical implications for avoiding sudden death in patients with high risk of plaque rupture. We report on multimodality imaging of ex-vivo human carotid plaque samples using a system that integrates fluorescence lifetime imaging (FLIM), ultrasonic backscatter microscopy (UBM), and photoacoustic imaging (PAI). Biochemical composition is differentiated with a high temporal resolution and sensitivity at the surface of the plaque by the FLIM subsystem. 3D microanatomy of the whole plaque is reconstructed by the UBM. Functional imaging associated with optical absorption contrast is evaluated from the PAI component. Simultaneous recordings of the optical, ultrasonic, and photoacoustic data present a wealth of complementary information concerning the plaque composition, structure, and function that are related to plaque vulnerability. This approach is expected to improve our ability to study atherosclerotic plaques. The multimodal system presented here can be translated into a catheter based intraluminal system for future clinical studies.     

Bioconjugated gold nanoparticles as a molecular based contrast agent: implications for imaging of deep tumors using optoacoustic tomography.

PURPOSE: Optoacoustic tomography (OAT) is a novel medical imaging method that uses optical illumination and ultrasonic detection to produce deep tissue images based on their light absorption. Abnormal angiogenesis in advanced tumors, that increases the blood content of the tumor, is an endogenous contrast agent for OAT. In early stages, however, angiogenesis is not sufficient to differentiate a tumor from normal tissue; justifying the application of an exogenous contrast agent. We have developed a molecular based contrast agent composed of gold nanoparticles conjugated to a monoclonal antibody that improves OAT imaging to potentiate its use in imaging deep tumors in early stages of cancer or metastatic lesions. PROCEDURE: Due to their strong optoacoustic signal, we used gold nanoparticles (NPs) as a contrast agent. To target NPs to breast cancer cells, we conjugated NPs to a monoclonal antibody that specifically binds cell surface receptors known to be overexpressed in human breast tumors. RESULTS: In a series of in vitro experiments, Herceptin (monoclonal antibody that binds HER2/neu) conjugated to 40 nm NPs (Mab/NPs) selectively targeted human SK-BR-3 breast cancer cells. The breast cancer cells were detected and imaged by OAT in a gelatin phantom that optically resembled breast tissue. Sensitivity experiments showed that a concentration as low as 10(9) NPs per ml were detectable at a depth of 6 cm. CONCLUSION: Experimental data together with theoretical analysis demonstrate the feasibility of detection of deeply seeded small tumors that express tumor associated antigens using targeted gold NPs and OAT.     

光学成像技术在乳腺病变诊断中的应用及进展

光学成像技术是近年来发展的一种新的功能成像技术。该技术通过对组织血红蛋白浓度及血氧饱和度的测量,反映肿块内部代谢状况,从而为乳腺病变的诊断和鉴别诊断提供重要信息,具有很高的临床应用价值。本文就光学成像技术的发展及其在乳腺病变诊断中的应用与最新研究进展进行综述。